Semiconductor integrated circuit, operating method thereof, and electronic device including the same

ABSTRACT

A semiconductor integrated circuit may include a recharge switch and a Wireless Recharge/MST unit. The recharge switch is connected with a battery through an intermediate node and provides a current path for wirely charging the battery in a wired charging mode. The Wireless Recharge/MST unit is connected between the intermediate node and a ground. The Wireless Recharge/MST unit disconnects the intermediate node and the ground in the wired charging mode, provides a wireless charging current to the battery through the intermediate node in a wireless charging mode, and is supplied with a current for generating a magnetic signal from the battery through the intermediate node in a magnetic secure transmission (MST) mode.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to Korean PatentApplication No. 10-2016-0141203 filed Oct. 27, 2016, in the KoreanIntellectual Property Office, the entire contents of which are herebyincorporated by reference.

BACKGROUND

Example embodiments of the inventive concepts disclosed herein relate toan integrated circuit. For example, at least some example embodimentsrelate to a semiconductor integrated circuit, an operating methodthereof, and/or an electronic device including the same.

Electronic devices, such as a smartphone, a mobile device, and a tablet,provide a user with various functions. Functions that an electronicdevice supports are increasing to cope with various demands of the user.An electronic device that supports a wireless charging function as wellas a wired charging function is emerging according to such a trend.

Also, the electronic device may support a payment function throughmagnetic secure transmission (MST). The MST-based payment functionreplaces existing card-type payments and provides the user with thepayment function through the electronic device. For this reason,electronic devices with the payment function are increasing.

However, an area of an electronic device, in particular, a mobile devicemay be limited due to a device characteristic. As such, there may berestrictions on mounting various components to perform various functionsin the mobile device. Accordingly, a semiconductor integrated circuitthat performs various functions while occupying a small area is needed.

SUMMARY

At least some example embodiments relate to a semiconductor integratedcircuit.

In some example embodiments, the semiconductor integrated circuitincludes a recharge switch connected to a battery through anintermediate node, the recharge switch configured selectively form acurrent path to wirely charge the battery, if the semiconductorintegrated circuit is operating in a wired charging mode; and a WirelessRecharge/MST device between the intermediate node and a ground, theWireless Recharge/MST device configured to, disconnect the intermediatenode and the ground, if the semiconductor integrated circuit isoperating in the wired charging mode, provide a wireless chargingcurrent to the battery through the intermediate node, if thesemiconductor integrated circuit is operating in a wireless chargingmode, and receive a current from the battery through the intermediatenode, if the semiconductor integrated circuit is operating in a magneticsecure transmission (MST) mode, the Wireless Recharge/MST deviceconfigured to generate a magnetic signal based on the current.

At least some example embodiments relate to a wired charging method of asemiconductor integrated circuit that supports a wired charging mode, awireless charging mode, and an MST mode.

In some example embodiments, the method includes setting thesemiconductor integrated circuit to the wired charging mode; turning offfirst and second switches, turning on a third switch and turning on afourth switch, the first and second switches being connected in parallelto an intermediate node of a Wireless Recharge/MST device included inthe semiconductor integrated circuit, the third switch being between thefirst switch and a ground, and the fourth switch being between thesecond switch and the ground; operating a linear charger, the linearcharger being between the intermediate node and a battery; and turningon a recharge switch, the recharge switch being between an externalpower source and the intermediate node.

At least some example embodiments relate to an electronic device.

In some example embodiments, the electronic device includes a battery; asemiconductor integrated circuit connected to the battery, thesemiconductor integrated circuit configured to support operations of awired charging mode of the battery, a wireless charging mode of thebattery, and a magnetic secure transmission (MST) mode; a transceiverconnected to the semiconductor integrated circuit, the transceiverconfigured to assist the semiconductor integrated circuit in thewireless charging mode and the MST mode; and a controller configured tocontrol the transceiver, the controller configured to, instruct, viacontrol signals, the semiconductor integrated circuit to provide acurrent to the battery, if the semiconductor integrated circuit isoperating in one of the wired charging mode and the wireless chargingmode, and instruct the battery to provide the semiconductor integratedcircuit with an MST current to generate a magnetic signal, if thesemiconductor integrated circuit is operating in the MST mode.

In some other example embodiments, the semiconductor integrated circuit(I/C) may include a tri-function device including a pair of I/Oterminals and an intermediate node, the tri-function device configuredto, charge a battery based on a charging current received via a wiredconnection between a first power source and the intermediate node, ifthe tri-function device is set to a wired charging mode, charge thebattery via a wireless connection between a transceiver and a secondpower source, the transceiver connected between the I/O terminals, ifthe tri-function device is set to a wireless charging mode, and transmitinformation to an external device via a wireless connection between thetransceiver and the external device, if the tri-function device is setto a magnetic secure transmission (MST) mode.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram illustrating a semiconductor integratedcircuit, according to an example embodiment of the inventive concepts;

FIG. 2 is a circuit diagram illustrating a recharge switch illustratedin FIG. 1;

FIG. 3 is a circuit diagram illustrating a Wireless Recharge/MST unitillustrated in FIG. 1;

FIG. 4 is a circuit diagram illustrating another embodiment of aWireless Recharge/MST unit illustrated in FIG. 1;

FIG. 5 is a circuit diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wired charging mode;

FIG. 6 is a flowchart illustrating for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wired charging mode;

FIGS. 7 and 8 are circuit diagrams for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wireless charging mode;

FIG. 9 is a flowchart illustrating for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wireless charging mode;

FIG. 10 is a circuit diagram illustrating a battery illustrated in FIGS.7 and 8;

FIG. 11 is a drawing illustrating an operation of a linear chargerillustrated in FIG. 1;

FIG. 12 is a circuit diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in an MST mode;

FIG. 13 is a timing diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in an MST mode;

FIGS. 14 and 15 are circuit diagrams for describing operations of asemiconductor integrated circuit of FIG. 1 in a first MST state and asecond MST state;

FIG. 16 is a flowchart illustrating an operation of a semiconductorintegrated circuit of FIG. 1 in an MST mode; and

FIG. 17 is a block diagram illustrating an electronic device including asemiconductor integrated circuit illustrated in FIG. 1.

DETAILED DESCRIPTION

Below, example embodiments of the inventive concepts may be described indetail and clearly to such an extent that an ordinary one in the arteasily implements the inventive concepts.

FIG. 1 is a block diagram illustrating a semiconductor integratedcircuit, according to an example embodiment of the inventive concepts.

Referring to FIG. 1, a semiconductor integrated circuit 100 may includea recharge switch 110, a Wireless Recharge/magnetic secure transmission(MST) unit (or, alternatively a tri-function device) 120, and a linearcharger 130.

The recharge switch 110 is connected between a charging terminal CHGINand a node n0. The recharge switch 110 forms a current path from thecharging terminal CHGIN to a terminal B+ in response to a control signalCTL[0]. To protect an overvoltage of the charging terminal CHGIN, overvoltage protection (OVP) (not illustrated) may be connected to thecharging terminal CHGIN.

The Wireless Recharge/MST unit 120 is connected between the node n0 anda terminal B−. The terminal B− is connected with a ground node GND. TheWireless Recharge/MST unit 120 may be connected with a transceiver (notillustrated) through a first input/output terminal C− and a secondinput/output terminal C+. The Wireless Recharge/MST unit 120 operates inresponse to control signals CTRL[1:4] to connect the node n0 and theterminal B− such that a current path to the terminal B+ through thelinear charger 130 is formed or to disconnect the node n0 and theterminal B−.

The linear charger 130 is connected between the node n0 and the terminalB+. The linear charger 130 may adjust the amount of current that flowstherethrough. While the example embodiment of FIG. 1 illustrates thelinear charger 130 Wireless Recharge/MST unit 120 included in thesemiconductor integrated circuit 100, example embodiment are not limitedthereto. For example, the linear charger 130 may be implemented in theform of a single chip that is separated from the Wireless Recharge/MSTunit 120. An operation of the linear charger 130 will be described withreference to FIGS. 10 and 11.

According to an example embodiment of the inventive concepts, thesemiconductor integrated circuit 100 may be implemented with one circuitthat supports a wired charging mode of operation, a wireless chargingmode of operation, and an MST mode of operation. Accordingly, the sizeof an electronic device (not illustrated) that includes thesemiconductor integrated circuit 100 may be reduced. Here, a battery(not illustrated) may be connected between the terminal B+ and theterminal B−. The semiconductor integrated circuit 100 operates to chargethe battery in the wired charging mode and the wireless charging mode.

For example, in the wired charging mode, an external power source (notillustrated) may be connected to the charging terminal CHGIN. In thiscase, the recharge switch 110 is controlled by the control signalCTRL[0] such that a current path from the charging terminal CHGIN to theterminal B+ is formed through the linear charger 130, and the WirelessRecharge/MST unit 120 is controlled by the control signals CTRL[1:4]such that a voltage of the ground node GND is not provided to the noden0. An operation of the wired charging mode of the semiconductorintegrated circuit 100 will be described with reference to FIGS. 5 and6.

In the wireless charging mode, the recharge switch 110 is turned off bythe control signal CTRL[0], and thus, no current flows through therecharge switch 110. In this case, the Wireless Recharge/MST unit 120 iscontrolled by the control signals CTRL[1:4] such that a current isprovided from the node n0 to the terminal B+ by external power from thetransceiver that may be connected to the first input/output terminal C−and the second input/output terminal C+. An operation of the wirelesscharging mode of the semiconductor integrated circuit 100 will bedescribed with reference to FIGS. 7 to 9.

The MST is a technology that allows a credit card payment terminal toautomatically load credit card information stored in an electronicdevice when the electronic device containing the credit card informationand the credit card payment terminal (e.g., a POS terminal) directly orindirectly contact each other, for payment. According to the MSTtechnology, the credit card information is transmitted to the creditcard payment terminal through a magnetic signal. According to an exampleembodiment, in the MST mode, the semiconductor integrated circuit 100operates to generate the magnetic signal.

In the MST mode, the recharge switch 110 is turned off by the controlsignal CTRL[0], and thus, no current flows through the recharge switch110. In this case, the Wireless Recharge/MST unit 120 is controlled bythe control signals CTRL[1:4] such that a current is provided to thetransceiver connected to the first input/output terminal C− and thesecond input/output terminal C+ for generation of the magnetic signal.An operation of the semiconductor integrated circuit 100 in the MST modewill be described with reference to FIGS. 12 to 16.

FIG. 2 is a circuit diagram illustrating a recharge switch illustratedin FIG. 1.

Referring to FIG. 2, the recharge switch 110 may include a main switchSW0 and a diode D0.

The main switch SW0 may be implemented with an NMOS transistor that iscontrolled by the control signal CTRL[0]. An anode of the diode D0 isconnected with the charging terminal CHGIN, and a cathode thereof isconnected with the node n0. The diode D0 may be a parasitic diode of theNMOS transistor. In this case, the recharge switch 110 may be configuredsuch that a source terminal of the NMOS transistor is connected to thecharging terminal CHGIN and a drain terminal thereof is connected to thenode n0. Even when the recharge switch 110 is turned off, an unintendedleakage current from the node n0 to the charging terminal CHGIN isprevented by the diode D0.

However, example embodiments are not limited to those illustrated inFIG. 2. For example, the recharge switch 110 may be implemented with aPMOS transistor. Alternatively, the recharge switch 110 may beimplemented with NMOS transistors or PMOS transistors that are connectedin a cascade form. However, example embodiments of the inventiveconcepts may not be limited thereto. For example, the recharge switch110 may be implemented with all forms of switches.

FIG. 3 is a circuit diagram illustrating a Wireless Recharge/MST unitillustrated in FIG. 1.

Referring to FIG. 3, a Wireless Recharge/MST unit 120 a may includefirst to fourth switches SW1 to SW4 and first to fourth diodes D1 to D4.

The first switch SW1 forms a current path between the node n0 and thefirst input/output terminal C− in response to the control signalCTRL[1]. The first switch SW1 may be implemented with a PMOS transistorthat is controlled by the control signal CTRL[1]. An anode of the firstdiode D1 is connected with the first input/output terminal C−, and acathode thereof is connected with the node n0.

The second switch SW2 forms a current path between the node n0 and thesecond input/output terminal C+ in response to the control signalCTRL[2]. The second switch SW2 may be implemented with a PMOS transistorthat is controlled by the control signal CTRL[2]. An anode of the seconddiode D2 is connected with the second input/output terminal C+, and acathode thereof is connected with the node n0.

Each of the first and second diodes D1 and D2 may be a parasitic diodeof the corresponding PMOS transistor. In this case, the first switch SW1may be configured such that a source terminal of the corresponding PMOStransistor is connected to the node n0 and a drain terminal thereof isconnected to the first input/output terminal C−. Also, the second switchSW2 may be configured such that a source terminal of the correspondingPMOS transistor is connected to the node n0 and a drain terminal thereofis connected to the second input/output terminal C+. In an exampleembodiment, an unintended leakage current from the node n0 to the firstinput/output terminal C− or the second input/output terminal C+ isprevented by the diodes D1 and D2 when the semiconductor integratedcircuit 100 of FIG. 1 operates in the wired charging mode.

The third switch SW3 forms a current path between the first input/outputterminal C− and the terminal B− in response to the control signalCTRL[3]. The third switch SW3 may be implemented with an NMOS transistorthat is controlled by the control signal CTRL[3]. An anode of the thirddiode D3 is connected with the terminal B− and a cathode thereof isconnected with the first input/output terminal C−.

The fourth switch SW4 forms a current path between the secondinput/output terminal C+ and the terminal B− in response to the controlsignal CTRL[4]. The fourth switch SW4 may be implemented with an NMOStransistor that is controlled by the control signal CTRL[4]. An anode ofthe fourth diode D4 is connected with the terminal B− and a cathodethereof is connected with the second input/output terminal C+. Each ofthe third and fourth diodes D3 and D4 may be a parasitic diode of thecorresponding NMOS transistor.

In another example embodiment, the first and second switches SW1 and SW2may be respectively implemented with NMOS transistors, and the third andfourth switches SW3 and SW4 may be respectively implemented with PMOStransistors. Alternatively, the first to fourth switches SW1 to SW4 maybe implemented with NMOS transistors or PMOS transistors that areconnected in a cascade form. However, example embodiments of theinventive concepts may not be limited thereto. For example, the first tofourth switches SW1 to SW4 may be implemented with all forms ofswitches.

As described above, the Wireless Recharge/MST unit 120 a may beconnected with a transceiver (not illustrated) through the firstinput/output terminal C− and the second input/output terminal C+ and mayoperate in the wireless charging mode or MST mode together with thetransceiver.

FIG. 4 is a circuit diagram illustrating the Wireless Recharge/MST unitillustrated in FIG. 1 according to another example embodiment.

Referring to FIG. 4, a Wireless Recharge/MST unit 120 b may include thefirst to fourth switches SW1 to SW4, the first to fourth diodes D1 toD4, and a capacitor C0. An operation and a configuration of the WirelessRecharge/MST unit 120 b of FIG. 4 is the same as those of the WirelessRecharge/MST unit 120 a of FIG. 3 except for the capacitor C0. Below, adescription thereof is thus omitted.

The capacitor C0 is connected between the node n0 and the terminal B−.The capacitor C0 eliminates noise, such as a ripple of a voltage formedat the node n0, when the Wireless Recharge/MST unit 120 b operates inthe wireless charging mode together with a transceiver (notillustrated). For example, instead of the capacitor C0, a high-passfilter for removing noise of a high band that is generated at the noden0 may be connected between the node n0 and the terminal B−. In thiscase, the high-band noise generated at the node n0 may be removedthrough the ground node GND that is connected with the terminal B−.

Below, for ease of description, the Wireless Recharge/MST unit 120 a ofFIG. 3 will be described as an example.

FIG. 5 is a circuit diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wired charging mode.

Referring to FIG. 5, in the wired charging mode, the semiconductorintegrated circuit 100 forms a current path from the charging terminalCHGIN to a battery 200 to charge the battery 200. Also, thesemiconductor integrated circuit 100 is controlled such that a voltageof the ground node GND is not provided to the node n0. Here, it isassumed that an external power source (not illustrated) is connected tothe charging terminal CHGIN such that the semiconductor integratedcircuit 100 enters the wired charging mode.

In the wired charging mode, the recharge switch 110 is turned on by thecontrol signal CTRL[0]. Also, the linear charger 130 is activated, andthus, a charging current Ic is supplied to the battery 200 from theexternal power source through the recharge switch 110 and the linearcharger 130. The battery 200 is charged by the supplied charging currentIc.

Also, the first and second switches SW1 and SW2 are turned off by thecontrol signals CTRL[1:2], and the third and fourth switches SW3 and SW4are turned on by the control signals CTRL[3:4]. The charging current Icis prevented from flowing to the ground node GND by the turned-off firstand second switches SW1 and SW2.

The third and fourth switches SW3 and SW4 are turned on because, forexample, if the third and fourth switches SW3 and SW4 are turned off,the first and second input/output terminals C− and C+ are floated. Inthis case, a voltage between the first and second input/output terminalsC− and C+ may be unpredictable due to a voltage of the node n0, a noiseof the ground node GND, an external noise, or the like. When a voltagedifference between the first and second input/output terminals C− and C+and the node n0 is larger than a diode threshold voltage at which thefirst diode D1 or the second diode D2 is turned on, the first diode D1or the second diode D2 may be turned on, and thus, the node n0 may beconnected with the first input/output terminal C− or the secondinput/output terminal C+. In this case, the charging current Ic may beleaked through a path between the node n0 and the first input/outputterminal C− or the second input/output terminal C+, not a wired chargingpath of the battery 200.

Accordingly, according to an example embodiment, the semiconductorintegrated circuit 100 may activate the third and fourth switches SW3and SW4 such that a uniform ground voltage is provided to the first andsecond input/output terminals C− and C+. As such, since the first diodeD1 or the second diode D2 is reversely biased, a leakage current pathbetween the node n0 and the first input/output terminal C− or the secondinput/output terminal C+ may be blocked.

The linear charger 130 may adjust the charging current Ic such that auniform amount of current is supplied to the battery 200. Also, thelinear charger 130 monitors a voltage of the terminal B+ to prevent thebattery 200 from being overcharged.

FIG. 6 is a flowchart illustrating for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wired charging mode.Below, how the semiconductor integrated circuit 100 operates in thewired charging mode will be described with reference to FIGS. 1 and 5.

Referring to FIGS. 1, 5 and 6, the semiconductor integrated circuit 100may charge the battery 200 by using an external power source (notillustrated) that is wirely connected therewith.

In operation S110, the semiconductor integrated circuit 100 enters thewired charging mode. For example, the semiconductor integrated circuit100 may enter the wired charging mode when the external power source isphysically connected to the charging terminal CHGIN of the semiconductorintegrated circuit 100.

In operation S120, the first and second switches SW1 and SW2 of theWireless Recharge/MST unit 120 a are turned off, and the third andfourth switches SW3 and SW4 thereof are turned on. In this case, thenode n0 is prevented from being connected with the ground node GND. Inoperation S130, the linear charger 130 is activated. As such, apreparation for supplying the charging current Ic to the battery 200 iscompleted before the recharge switch 110 is turned on.

In operation S140, the main switch SW0 of the recharge switch 110 isturned on. In this case, the charging current Ic that is supplied fromthe external power source connected with the charging terminal CHGIN issupplied to the battery 200 through the recharge switch 110 and thelinear charger 130. The battery 200 is charged by the supplied chargingcurrent Ic.

FIGS. 7 and 8 are circuit diagrams for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wireless charging mode.

Referring to FIGS. 7 and 8, the semiconductor integrated circuit 100,the battery 200, a transceiver 300, and a recharge unit 400 areillustrated. The semiconductor integrated circuit 100 and the battery200 are configured the same as those of FIG. 5, and a descriptionthereof is thus omitted.

The semiconductor integrated circuit 100 may perform wireless chargingby for example, using the following: a magnetic induction way, amagnetic resonance way, or an antenna way. The magnetic induction wayrefers to a way to charge using electromagnetic induction betweeninductors. The magnetic resonance way refers to a way to charge usingmagnetic resonance between inductors having the same resonant frequency.The antenna way refers to a way to charge using far field radiation ofan antenna.

Hereinafter, an example embodiment is described in which thesemiconductor integrated circuit 100 uses a wireless charging way, whichcorresponds to the magnetic induction way, in the wireless chargingmode. The above assumption is only an example, and example embodimentsof the inventive concepts may not be limited thereto.

The transceiver 300 is connected with the first and second input/outputterminals C− and C+ of the Wireless Recharge/MST unit 120 a. Thetransceiver 300 may convert power transmitted from the recharge unit 400into an induced current Id and may supply the induced current Id to theWireless Recharge/MST unit 120 a. The transceiver 300 may include afirst inductor L1 for inducing the induced current Id from the powertransmitted from the recharge unit 400. Here, inductance of the firstinductor L1 may change with design factors such as an operatingfrequency, a power transfer efficiency, etc. of the recharge unit 400,and, thus, may be determined empirically.

The example embodiment of FIGS. 7 and 8 illustrate the transceiver 300as including only the first inductor L1. However, example embodimentsare not limited thereto and the configuration of FIGS. 7 and 8 is onlyan example. For example, the transceiver 300 may include any circuit forinducing the induced current Id from the power transmitted from therecharge unit 400.

The recharge unit 400 may be implemented with a separate device that isseparated from the semiconductor integrated circuit 100, the battery200, and the transceiver 300. For example, the recharge unit 400 maytransmit power to the semiconductor integrated circuit 100 only when therecharge unit 400 is spaced apart from the transceiver 300 by a distanceor more. Alternatively, the recharge unit 400 may transmit power to thesemiconductor integrated circuit 100 within a distance from thetransceiver 300. The recharge unit 400 may include a second inductor L2and an alternating current (AC) power source Vr. The recharge unit 400may generate a wireless charging current Ir by using the AC power sourceVr. The wireless charging current Ir may have a phase that varies with avoltage phase of the AC power source Vr. Here, for ease of description,the recharge unit 400 is illustrated as only including the secondinductor L2 and the AC power source Vr. The configuration of therecharge unit 400 is only one example. The recharge unit 400 may includeany component(s) for generating the wireless charging current Ir, suchas a resistor for determining the amount of wireless charging currentIr.

Below, an operation in which the semiconductor integrated circuit 100wirelessly charges the battery 200 is described. First, the wirelesscharging current Ir is generated by the AC power source Vr of therecharge unit 400, and a magnetic field is formed by a phase variationof the wireless charging current Ir. When the magnetic field is formed,the induced current Id is generated through the first inductor L1 of thetransceiver 300. A phase of the induced current Id may vary with a phaseof the wireless charging current Ir, and a difference between phases ofthe induced current Id and the wireless charging current Ir may be 180degrees.

A connection relationship of the Wireless Recharge/MST unit 120 achanges with a phase of the induced current Id, and even though a phaseof the induced current Id flowing in the transceiver 300 changes, aphase of the induced current Id provided to the battery 200 may bemaintained within a uniform range by the changed connectionrelationship. Here, two states are defined according to a phase of theinduced current Id. Below, a first state refers to the case that adirection of the induced current Id is a direction from the firstinput/output terminal C− to the second input/output terminal C+. Asecond state refers to the case that a direction of the induced currentId is a direction from the second input/output terminal C+ to the firstinput/output terminal C−.

Referring to FIG. 7, a connection relationship of the WirelessRecharge/MST unit 120 a in the first state is illustrated. In the firststate, the first and fourth switches SW1 and SW4 are turned off by thecontrol signals CTRL[1] and CTRL[4], and the second and third switchesSW2 and SW3 are turned on by the control signals CTRL[2] and CTRL[3]. Inthis case, a first induction loop Loop_d1 that includes the third switchSW3, the first inductor L1, the second switch SW2, and the linearcharger 130 is formed. That is, in the first state, the induced currentId flows along the first induction loop Loop_d1, and the battery 200 ischarged by the induced current Id provided to the terminal B+.

Referring to FIG. 8, a connection relationship of the WirelessRecharge/MST unit 120 a in the second state is illustrated. In thesecond state, the first and fourth switches SW1 and SW4 are turned on bythe control signals CTRL[1] and CTRL[4], and the second and thirdswitches SW2 and SW3 are turned off by the control signals CTRL[2] andCTRL[3]. In this case, a second induction loop Loop_d2 that includes thefourth switch SW4, the first inductor L1, the first switch SW1, and thelinear charger 130 is formed. That is, in the second state, the inducedcurrent Id flows along the second induction loop Loop_d2, and thebattery 200 is charged by the induced current Id provided to theterminal B+.

In FIGS. 7 and 8, the recharge switch 110 is turned off by the controlsignal CTRL[0]. Accordingly, it may be possible to prevent the inducedcurrent Id from being leaked to the charging terminal CHGIN through therecharge switch 110. With the above description, the induced current Idinduced by the recharge unit 400 is provided to the battery 200 throughthe terminal B+ in the same current direction, and the battery 200 ischarged by the induced current Id.

FIG. 9 is a flowchart illustrating for describing an operation of asemiconductor integrated circuit of FIG. 1 in a wireless charging mode.Below, a flowchart illustrated in FIG. 9 will be described withreference to FIGS. 1, 7, and 8.

Referring to FIGS. 1 and 7 to 9, the semiconductor integrated circuit100 may charge the battery 200 by using the induced current Id inducedby the transceiver 300.

In operation S210, the semiconductor integrated circuit 100 enters thewireless charging mode. For example, the semiconductor integratedcircuit 100 may enter the wireless charging mode when the semiconductorintegrated circuit 100 approaches the recharge unit 400 within a uniformdistance.

In operation S220, the main switch SW0 of the recharge switch 110 isturned off.

In operation S230, the linear charger 130 is activated. As such, apreparation for supplying the induced current Id to the battery 200 iscompleted before the Wireless Recharge/MST unit 120 a performs awireless charging operation.

In operation S240, the first to fourth switches SW1 to SW4 of theWireless Recharge/MST unit 120 a perform the wireless charging operationof FIG. 7 or 8 in response to the control signals CTRL[1] to CTRL[4]. Inthis case, the battery 200 is charged by the supplied induced currentId.

FIG. 10 is a circuit diagram illustrating a battery illustrated in FIGS.7 and 8.

Referring to FIG. 10, a configuration of a modeling circuit of thebattery 200 is illustrated. The battery 200 may include a parasiticresistor Rb and a capacitor Cb. The parasitic resistor Rb may correspondto a resistor indicating a parasitic component that is generated in theprocess of manufacturing the battery 200. The capacitor Cb is connectedwith the parasitic resistor Rb through a node n1. The capacitor Cbstores charges by the charging current Ic of FIG. 5 or the inducedcurrent Id of FIGS. 7 and 8, and the charges are stored in the capacitorCb in the form of a voltage. For example, the battery 200 may include aLi-ion battery or a Li-polymer battery.

FIG. 11 is a drawing illustrating an operation of a linear chargerillustrated in FIG. 1. Below, an operation of a linear chargerillustrated in FIG. 11 will be described with reference to FIGS. 5, 7,8, and 10.

Referring to FIGS. 5, 7, 8, 10 and 11, operations of the linear charger130 in the wired charging mode and the wireless charging mode are asfollows.

During a time interval between t0 and t1, the linear charger 130operates in a constant current mode. In the constant current mode, thelinear charger 130 adjusts the amount of the charging current Ic of thewired charging mode or the induced current Id of the wireless chargingmode such that a uniform amount of current is provided to the battery200. This is to prevent the battery 200 from being broken down by anexcessive current.

In the time interval between t0 and t1, a uniform voltage difference ismaintained between a voltage V(B+) and a voltage V(n1). The voltagedifference is generated due to a current flowing to the battery 200 andthe parasitic resistor Rb in the time interval between t0 and t1. Thatis, an internal voltage V(n1) of the battery 200 may be determined by avoltage drop, which is generated due to the charging current Ic or theinduced current Id with parasitic resistor Rb, and the voltage V(B+).That is, V(n1)=V(B+)−(Ic*Rb) in the wired charging mode, andV(n1)=V(B+)−(Id*Rb) in the wireless charging mode.

During a time interval between t1 and t2, the linear charger 130operates in a constant voltage mode. When the voltage V(B+) is not lessthan a target voltage Vtarget, the linear charger 130 enters theconstant voltage mode. That is, at t1, the linear charger 130 enters theconstant voltage mode by detecting that the voltage V(B+) reaches thetarget voltage Vtarget.

The reason that the linear charger 130 maintains the constant voltagemode during a given time is as follows. Even though the voltage V(B+)reaches the target voltage Vtarget at t1, a voltage of the internal noden1 of the battery 200 fails to reach the target voltage Vtarget due to avoltage drop by the parasitic resistor Rb. The voltage V(n1) may reachthe target voltage Vtarget after a time that corresponds to RC delaydetermined by the parasitic resistor Rb and the capacitor Cb. The linearcharger 130 operates in the constant voltage mode, in which the targetvoltage Vtarget is maintained during a time interval between t1 and t2,to secure a time when the voltage V(n1) reaches the target voltageVtarget.

After a point in time t2, to prevent the battery 200 from beingovercharged and a charged voltage from being discharged, the linearcharger 130 may operate to separate the terminal B+ from the node n0.

FIG. 12 is a circuit diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in an MST mode.

Referring to FIG. 12, the semiconductor integrated circuit 100, thebattery 200, the transceiver 300, and a point of sale (POS) device 500are illustrated. The semiconductor integrated circuit 100 and thebattery 200 are configured the same as those of FIG. 5, and adescription thereof is thus omitted.

The MST is a technology that emits a magnetic signal that mimics themagnetic strip on a traditional payment card. The MST sends a magneticsignal from an electronic device of a user to the payment terminal'scard reader (to emulate swiping a physical card without having toupgrade the terminal's software or hardware). Payment information mayinclude a primary account number (PAN), a device account number (DAN),virtual credit card information, a bank information number (BIN), a cardsecurity code (CSC), a card verification value (CVV), or cryptogram.

The transceiver 300 is connected with the first and second input/outputterminals C− and C+ of the Wireless Recharge/MST unit 120 a. In the MSTmode, the transceiver 300 may generate a magnetic field “B” through anMST current Im from the battery 200 and may transmit the generatedmagnetic field “B” to the POS device 500 as a magnetic signal. Thetransceiver 300 may include a third inductor L3 that generates themagnetic field “B” through the MST current Im from the battery 200.Here, inductance of the third inductor L3 may change with variousfactors including a way to transmit an MST signal.

In the example embodiment of FIG. 12, the transceiver 300 is illustratedas including only the third inductor L3. However, the configuration ofFIG. 12 is only one example. The transceiver 300 may include any circuitfor generating the magnetic field “B” through the MST current Im. In anexample embodiment, the transceiver 300 of FIG. 12 may be configured tobe different from the transceiver of FIG. 5. The POS device 500 receivesdata through a magnetic signal, which includes payment information,transmitted in the form of the magnetic field “B” and processes thereceived data.

An operation in which the semiconductor integrated circuit 100 generatesa magnetic signal in the MST mode is described below. The magneticsignal is generated when the MST current Im varies with time.Accordingly, the Wireless Recharge/MST unit 120 a increases or decreasesthe MST current Im based on the transmitted data. A periodic variationof the MST current Im may define a period of the magnetic signal. Theperiod of the magnetic signal may be variable. That is, a waveform ofthe magnetic signal may include an interval that has a first periodshorter than a reference period and an interval that has a second periodlonger than the reference period. For example, the magnetic signal ofthe first period may mean logic “1”, and the magnetic signal of thesecond period may mean logic “0”. Alternatively, the magnetic signal ofthe first period may mean logic “0”, and the magnetic signal of thesecond period may mean logic “1”. The period of the magnetic signal maybe controlled by a control timing of the control signals CTRL[1:4].

The first and second periods of the magnetic signal may be changed inconsideration of a design or device characteristic. In FIG. 12, themagnetic field “B” is illustrated as being generated counterclockwise.However, the direction of the magnetic field “B” is only one example.The direction of the magnetic field “B” may change with a direction ofthe MST current Im flowing to the third inductor L3 or a direction ofwinding the third inductor L3.

A connection relationship of the Wireless Recharge/MST unit 120 changeswith a phase of the MST current Im, and thus, a direction or phase ofthe MST current Im from the transceiver 300 may change. Here, twostates, that is, a first MST state and a second MST state, are definedaccording to a phase of the MST current Im. The first MST state refersto the case that a direction of the MST current Im determined accordingto a phase change in the MST current Im is a direction from the firstinput/output terminal C− to the second input/output terminal C+. Thesecond MST state refers to the case that a direction of the MST currentIm determined according to a phase change in the MST current Im is adirection from the second input/output terminal C+ to the firstinput/output terminal C−.

FIG. 13 is a timing diagram for describing an operation of asemiconductor integrated circuit of FIG. 1 in an MST mode. Below, thetiming diagram illustrated in FIG. 13 will be described with referenceto FIG. 12.

Referring to FIGS. 12 and 13, the magnetic field “B” is generated as aphase of the MST current Im varies, and the generated magnetic field “B”may be transmitted to the POS device 500 as the magnetic signal.

During a time interval between t0 and t1, a phase of the MST current Imis inverted. That is, before t0, a direction of the MST current Im thatflows from the second input/output terminal C+ to the first input/outputterminal C− may change to flow from the first input/output terminal C−to the second input/output terminal C+. The connection relationship ofthe Wireless Recharge/MST unit 120 a is changed at the point in time t0,and thus, a phase of the MST current Im changes. As such, the magneticfield “B” is generated as a phase of the MST current Im changes in thetime interval between t0 and t1, and the generated magnetic field “B” istransmitted to the POS device 500 as the magnetic signal.

During a time interval between t1 and t2, a phase of the MST current Imis completely changed, and thus, a uniform amount of MST current Imflows in one direction. In this case, since the amount or phase of theMST current Im does not change, the magnetic field “B” may not begenerated. The time interval between t0 and t2 corresponds to the firstMST state.

During a time interval between t2 and t3, a phase of the MST current Imis again inverted. That is, before t2, a direction of the MST current Imthat flows from the first input/output terminal C− to the secondinput/output terminal C+ may change to flow from the second input/outputterminal C+ to the first input/output terminal C−. The change in a phaseof the MST current Im may be generated by the connection relationship ofthe Wireless Recharge/MST unit 120 a changed at the point in time t2Like the time interval between t0 and t1, the magnetic field “B” isgenerated as a phase of the MST current Im changes in the time intervalbetween t2 and t3, and the generated magnetic field “B” is transmittedto the POS device 500 as the magnetic signal.

During a time interval between t3 and t4, a phase of the MST current Imis completely changed, and thus, a uniform amount of MST current Imflows in one direction. Like the time interval between t1 and t2, sincethe amount or phase of the MST current Im does not change, the magneticfield “B” may not be generated. The time interval between t2 and t4corresponds to the second MST state.

After t4, the operation of the Wireless Recharge/MST unit 120 a and aphase change in the MST current Im are the same as described in the timeinterval between t0 and t4, and a description thereof is thus omitted.

FIGS. 14 and 15 are circuit diagrams for describing operations of asemiconductor integrated circuit of FIG. 1 in a first MST state and asecond MST state, respectively. In FIGS. 14 and 15, the recharge switch110 is turned off by the control signal CTRL[0]. Accordingly, it may bepossible to prevent the MST current Im from being leaked to the chargingterminal CHGIN.

Referring to FIG. 14, a connection relationship of the WirelessRecharge/MST unit 120 a in the first MST state is illustrated. In thefirst MST state, the first and fourth switches SW1 and SW4 are turnedoff by the control signals CTRL[1] and CTRL[4], and the second and thirdswitches SW2 and SW3 are turned on by the control signals CTRL[2] andCTRL[3]. In this case, a first MST loop Loop_m1 that includes the thirdswitch SW3, the third inductor L3, the second switch SW2, and the linearcharger 130 is formed. That is, the MST current Im flows along the firstMST loop Loop_m1 in the first MST state, and the transceiver 300generates a magnetic signal by a change in the amount or phase of theMST current Im from the battery 200.

Referring to FIG. 15, a connection relationship of the WirelessRecharge/MST unit 120 a in the second MST state is illustrated. In thesecond MST state, the first and fourth switches SW1 and SW4 are turnedon by the control signals CTRL[1] and CTRL[4], and the second and thirdswitches SW2 and SW3 are turned off by the control signals CTRL[2] andCTRL[3]. In this case, a second MST loop Loop_m2 that includes thefourth switch SW4, the third inductor L3, the first switch SW1, and thelinear charger 130 is formed. That is, the MST current Im flows alongthe second MST loop Loop_m2 in the second MST state, and the transceiver300 generates a magnetic signal by a change in the amount or phase ofthe MST current Im from the battery 200.

FIG. 16 is a flowchart illustrating an operation of a semiconductorintegrated circuit of FIG. 1 in an MST mode. The flowchart of FIG. 16will be described with reference to FIGS. 12 to 15. Referring to FIG.16, the semiconductor integrated circuit 100 may generate a magneticsignal by using the MST current Im provided from the battery 200.

In operation S310, the semiconductor integrated circuit 100 enters theMST mode. For example, the semiconductor integrated circuit 100 mayenter the MST mode when the semiconductor integrated circuit 100approaches the POS device 500 within a uniform distance.

In operation S320, the main switch SW0 of the recharge switch 110 isturned off.

In operation S330, the linear charger 130 is activated. Here, the linearcharger 130 may perform an operation that is different from the constantcurrent operation or the constant voltage operation described withreference to FIG. 11. That is, the linear charger 130 may operate as aswitch while being fully turned on, and thus, a voltage of the terminalB+ may be transmitted to the node n0 without change. Through operationS310 to operation S330, the Wireless Recharge/MST unit 120 a maycomplete the preparation for generating the magnetic signal.

In operation S340, the first to fourth switches SW1 to SW4 of theWireless Recharge/MST unit 120 a perform an operation of the MST mode ofFIGS. 12 to 15 in response to the control signals CTRL[1] to CTRL[4].Accordingly, the semiconductor integrated circuit 100 generates themagnetic signal together with the transceiver 300.

FIG. 17 is a block diagram illustrating an electronic device including asemiconductor integrated circuit illustrated in FIG. 1.

Referring to FIG. 17, an electronic device 1000 may include asemiconductor integrated circuit 1100, a battery 1200, a transceiver(Transmitter/Receiver) 1300, a controller 1400, and over voltageprotection (OVP) 1500. Configurations and operations of thesemiconductor integrated circuit 1100, the battery 1200, and thetransceiver 1300 are the same as described with reference to FIGS. 1 to16, and a description thereof is thus omitted.

The controller 1400 may include processing circuitry such as, but notlimited to, a processor, an application processor, a Central ProcessingUnit (CPU), a controller, an arithmetic logic unit (ALU), a digitalsignal processor, a microcomputer, a field programmable gate array(FPGA), an Application Specific Integrated Circuit (ASIC), aSystem-on-Chip (SoC), a programmable logic unit, a microprocessor, orany other device capable of performing operations in a defined manner.

Further, electronic device 1000 may include a memory (not shown). Thememory may include a nonvolatile memory device, a volatile memorydevice, a non-transitory storage medium, or a combination of two or moreof the above-mentioned devices. For example, the memory may include oneor more of a Read Only Memory (ROM), Random Access Memory (RAM), CompactDisk-Read Only Memories (CD-ROMs), magnetic tapes, floppy disks, and anoptical recording medium.

The processing circuitry may be configured, through a layout designand/or execution of computer readable instructions stored in the memory,as a special purpose computer to control the semiconductor integratedcircuit 1100 and the transceiver 1300.

For example, the controller 1400 may generate control signals CTRL[0:4]for controlling the semiconductor integrated circuit 1100 and mayprovide the generated control signals CTRL[0:4] to the semiconductorintegrated circuit 1100. The semiconductor integrated circuit 1100 mayperform operations of the wireless charging mode, the wired chargingmode, and the MST mode described with reference to FIGS. 1 to 16 inresponse to the control signals CTRL[0:4].

Further, for example, the controller 1400 may control the transceiver1300. For example, as described above, inductance or an additionalcircuit used according to an operation of the transceiver 1300 may varyin the wireless charging mode and the MST mode. In this case, thecontroller 1400 may control the transceiver 1300 such that aconfiguration of the transceiver 1300 is changed according to each mode.

The electronic device 1000 may include the OVP 1500 between the chargingterminal CHGIN and the semiconductor integrated circuit 1100. The OVP1500 may reduce (or, alternatively, prevent) an unintended excessivecurrent from flowing to the charging terminal CHGIN or the semiconductorintegrated circuit 1100. In FIG. 17, the OVP 1500 is illustrated asbeing included in the electronic device 1000. However, the configurationof FIG. 17 is only one example. The OVP 1500 may be separatelyimplemented outside the electronic device 1000.

According to an example embodiment of the inventive concepts, an areamay be reduced that is occupied by a circuit or electronic deviceoperating in a wired charging mode, a wireless charging mode, and an MSTmode. Accordingly, manufacturing costs may be reduced.

While the inventive concepts have been described with reference to someexample embodiments, it will be apparent to those skilled in the artthat various changes and modifications may be made without departingfrom the spirit and scope of the inventive concepts. Therefore, itshould be understood that the above example embodiments are notlimiting, but illustrative.

What is claimed is:
 1. A semiconductor integrated circuit comprising: arecharge switch connected to a battery through an intermediate node, therecharge switch configured selectively form a current path to wirelycharge the battery, if the semiconductor integrated circuit is operatingin a wired charging mode; and a Wireless Recharge/Magnetic SecureTransmission (MST) device between the intermediate node and a ground,the Wireless Recharge/MST device including at least a plurality ofswitches configured to, disconnect the intermediate node and the ground,if the semiconductor integrated circuit is operating in the wiredcharging mode, provide a wireless charging current to the batterythrough the intermediate node, if the semiconductor integrated circuitis operating in a wireless charging mode, and receive a current from thebattery through the intermediate node, if the semiconductor integratedcircuit is operating in a magnetic secure transmission (MST) mode, theWireless Recharge/MST device configured to generate a magnetic signalbased on the current received from the battery.
 2. The semiconductorintegrated circuit of claim 1, wherein the recharge switch is off, ifthe semiconductor integrated circuit is operating one of in the wirelesscharging mode and the MST mode.
 3. The semiconductor integrated circuitof claim 1, wherein the recharge switch comprises: an NMOS transistorhaving a drain terminal connected to the intermediate node.
 4. Thesemiconductor integrated circuit of claim 1, further comprising: alinear charger between the intermediate node and the battery.
 5. Thesemiconductor integrated circuit of claim 4, wherein the linear chargeris configured to, provide a uniform amount of current to the battery, ifthe semiconductor integrated circuit is operating in one of the wirelesscharging mode and the wired charging mode, and provide a voltage of thebattery to the Wireless Recharge/MST device through the intermediatenode, if the semiconductor integrated circuit is operating in the MSTmode.
 6. The semiconductor integrated circuit of claim 1, wherein theWireless Recharge/MST device is controlled by first to fourth controlsignals, and the plurality of switches included in the WirelessRecharge/MST device comprises: a first switch configured to provide acurrent path between the intermediate node and a first input/output(I/O) node in response to the first control signal; a second switchconfigured to provide a current path between the intermediate node and asecond I/O node in response to the second control signal; a third switchconfigured to provide a current path between the first I/O node and theground in response to the third control signal; and a fourth switchconfigured to provide a current path between the second I/O node and theground in response to the fourth control signal.
 7. The semiconductorintegrated circuit of claim 6, wherein each of the first switch and thesecond switch includes a PMOS transistor, and each of the third switchand the fourth switch includes an NMOS transistor.
 8. The semiconductorintegrated circuit of claim 6, wherein the first switch and secondswitch are off and the third switch and fourth switch are on, if thesemiconductor integrated circuit is operating in the wired chargingmode.
 9. The semiconductor integrated circuit of claim 6, wherein theWireless Recharge/MST device is connected to a transceiver, and thewireless Recharge/MST device configured to, receive the wirelesscharging current from the transceiver via the first I/O node and thesecond I/O node, if the semiconductor integrated circuit is operating inthe wireless charging mode, and provide the transceiver with a MSTcurrent via the first I/O node and the second I/O node, if thesemiconductor integrated circuit is operating in the MST mode, thetransceiver configured to generate the magnetic signal based on the MSTcurrent.
 10. The semiconductor integrated circuit of claim 9, wherein inthe wireless charging mode, the Wireless Recharge/MST device isconfigured to provide the wireless charging current to the batterythrough the intermediate node, the second switch is on, third switch ison, the first switch is off and the fourth switch is off, if a currentthrough the first I/O node, the transceiver, and the second I/O nodeflows in a first direction, and the second switch is off, the thirdswitch is off, the first switch is on and the fourth switch is on, ifthe current through the first I/O node, the transceiver, and the secondI/O node flows in a second direction, the second direction beingdifferent from the first direction.
 11. The semiconductor integratedcircuit of claim 9, wherein in the MST mode, the Wireless Recharge/MSTdevice is configured to receive the MST current from the battery throughthe intermediate node, the Wireless Recharge/MST device configured toinstruct the transceiver to generate the magnetic signal from the MSTcurrent, the second switch is on, third switch is on, the first switchis off and fourth switch is off, if a current through the first I/Onode, the transceiver, and the second I/O node flows in a firstdirection, and the second switch is off, the third switch is off, thefirst switch is on and fourth switch is on, if the current through thefirst I/O node, the transceiver, and the second I/O node flows in asecond direction, the second direction being different from the firstdirection.
 12. The semiconductor integrated circuit of claim 6, whereinthe Wireless Recharge/MST device further comprises: a capacitor betweenthe intermediate node and the ground.
 13. The semiconductor integratedcircuit of claim 6, further comprising: a linear charger between theintermediate node and the battery.